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The problem of scheduling Compal S.A.'s production of perishable goods is examined. Since the problem's objective functions are conflicting and the commodity is subject to seasonal demand, it is decomposed into two sub-problems, namely, annual planning and short-term scheduling. For these, linear programming and integer programming models are derived, respectively, and a two-stage heuristic is developed.

A study was conducted to examine a proposal of the design for a cellular structure to solve the planning and control problem. The study applies objective oriented methods for the problem's specification and design. The proposal is then applied to flow-shop and job scheduling problems involving various numbers of lots and machines. Results show that the proposed model exhibits potential solutions following those of existing heuristic and exact techniques.

Introduction: The magnitude of the secondary response to chronic respiratory acidosis, that is, change in plasma bicarbonate concentration ([HCO 3 - ]) per mm Hg change in arterial carbon dioxide tension (PaCO 2 ), remains uncertain. Retrospective observations yielded Δ[HCO 3 - ]/ΔPaCO 2 slopes of 0.35 to 0.51 mEq/l per mm Hg, but all studies have methodologic flaws., Methods: We studied prospectively 28 stable outpatients with steady-state chronic hypercapnia. Patients did not have other disorders and were not taking medications that could affect acid-base status. We obtained 2 measurements of arterial blood gases and plasma chemistries within a 10-day period., Results: Steady-state PaCO 2 ranged from 44.2 to 68.8 mm Hg. For the entire cohort, mean (± SD) steady-state plasma acid-base values were as follows: PaCO 2 , 52.8 ± 6.0 mm Hg; [HCO 3 - ], 29.9 ± 3.0 mEq/l, and pH, 7.37 ± 0.02. Least-squares regression for steady-state [HCO 3 - ] versus PaCO 2 had a slope of 0.476 mEq/l per mm Hg (95% CI = 0.414-0.538, P  < 0.01; r  = 0.95) and that for steady-state pH versus PaCO 2 had a slope of -0.0012 units per mm Hg (95% CI = -0.0021 to -0.0003, P  = 0.01; r  = -0.47). These data allowed estimation of the 95% prediction intervals for plasma [HCO 3 - ] and pH at different levels of PaCO 2 applicable to patients with steady-state chronic hypercapnia., Conclusion: In steady-state chronic hypercapnia up to 70 mm Hg, the Δ[HCO 3 - ]/ΔPaCO 2 slope equaled 0.48 mEq/l per mm Hg, sufficient to maintain systemic acidity between the mid-normal range and mild acidemia. The estimated 95% prediction intervals enable differentiation between simple chronic respiratory acidosis and hypercapnia coexisting with additional acid-base disorders.

Background: Cognitive behavioral therapy (CBT) has proven useful in treating fibromyalgia, depression, and anxiety. Computerized delivery of CBT allows increased access to such therapy. This study assessed the effect of internet-based CBT on Fibromyalgia Impact Questionnaire (FIQ) composite scores and tender point assessments., Methods: This 12-week randomized controlled trial included patients ≥18 years of age with 1990 American College of Rheumatology criteria for fibromyalgia and mild to moderate depression and anxiety. A total of 56 subjects were randomized into either a 6-week internet-based CBT group (MoodGYM) or a control group (standard care). We evaluated patients in both groups at 1-, 6-, and 12-week follow-up. The primary outcome measure was change in FIQ composite score. A secondary outcome measure was change in tender point assessment., Results: The mean age of study participants was 55 years, and 88% were female. Mean FIQ scores were significantly lower in the MoodGYM group compared to the control group (P<0.05 for group differences at 6 and 12 weeks). Mean tender point scores were also significantly lower in the MoodGYM group (P<0.001 at 6 and 12 weeks). We found no significant difference in the FIQ scores across the 3 timepoints in the MoodGYM group, but tender points showed a significant negative trend from baseline to 12-week follow-up., Conclusion: Patients in the internet-based MoodGYM CBT program had lower FIQ and tender point scores at 6- and 12-week follow-up. Internet-based CBT could be beneficial in the treatment of mild to moderate depression and anxiety in patients with fibromyalgia by allowing increased access to CBT.

The study of nasal ciliary beat frequency (CBF) and ultrastructure may contribute to the understanding of pathognomonic cases of male infertility associated with defects in sperm motility. This study was designed to report a particular case of male infertility, characterized by the association of two respiratory autosomal recessive genetic diseases (alpha-1-antitrypsin deficiency [AAT-D] and primary ciliary dyskinesia [PCD]). A 39-year-old patient with complete sperm immotility, AAT-D, and bronchiectasis was studied in the Laboratory of Male Fertility, the Department of Urology, the Respiratory Center of a Pediatric Hospital, and in the Department of Clinical Medicine of a Rehabilitation Respiratory Hospital. Family history, physical examination, hormonal analysis, microbial assays, semen analysis, nasal ciliary function, and structure study by digital high-speed video photography and transmission electron microscopy are described. A noninvasive nasal biopsy to retrieve ciliated epithelium lining the inferior surface of the inferior nasal turbinates was performed and CBF was determined. Beat pattern was slightly curved and rigid, not wide, and metacronic in all the observed fields analyzed. CBF was 8.2 Hz in average (reference value, 10-15 Hz) Ultrastructural assay revealed absence of the inner dynein arms in 97% of the cilia observed. The final infertility accurate diagnosis was achieved by the study of nasal CBF and ultrastructure contributing to the patient health management and genetic counseling while deciding fatherhood. Beyond this particular case, the present report may open a new field of studies in male infertility, mainly in cases of asthenozoospermia.